US Patent 7177320 Transfer of data in a telecommunications system

A telecommunications system comprises a transmitter within the central terminal for sending a data message destined for a particular subscriber terminal over communication channels as a number of data blocks. A frame generator is provided within the central terminal for generating a number of frames to represent each data block, each frame having a header portion and data portion. The header portion is arranged to be transmitted in a fixed format chosen to facilitate reception of the header portion by each subscriber terminal, and is arranged to include a number of control fields for providing information about the data portion. The data portion is arranged to be transmitted in a variable format.